Device for decreasing interference in cable bundle and method thereof

ABSTRACT

Disclosed is a device and method for decreasing interference in a cable bundle. The device includes a plurality of concentration devices, an interference measurer, and a concentration device. Each concentration device accesses an uplink and provides a network service to a terminal through a cable bundle in an access section. An interference measurer is connected between the cable bundle and the terminal. The interference measure is configured to measure an interference signal by measuring a signal transmitted to the terminal through the cable bundle, calculate an interference coefficient for generating a quasi-interference signal, and transmit the same to the concentration devices. The concentration devices is configured to calculate an additional signal for offsetting an interference signal by using the interference coefficient, add the additional signal to the original signal, and transmit the additional signal to the cable bundle.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2015-0081398 filed in the Korean IntellectualProperty Office on Jun. 9, 2015, the entire contents of which areincorporated herein by reference.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

The present disclosure relates to a device and method for decreasinginterference in a cable bundle.

(b) Description of the Related Art

An x digital subscriber line (xDSL) using cables and a fiber to the x(FTTx) using optic cables are representative systems for providing a 100mega-based high-speed Internet service.

Recently, Internet service providers (ISPs) have been competing witheach other so as to overcome the speed limit and provide a faster speed,such as the giga-level Internet. For example, the FTTx is therepresentative service providing system.

Technologies for providing giga-level speeds using existing lines aswell as the FTTx have been developed and the services have beenprepared.

Many studies have conducted for overcoming problems, such as speeddeterioration issues with respect to interference, particularly,crosstalk, when the services are provided through lines. However, thecrosstalk still exists.

Particularly, the access network uses a cable bundle wrapped with aplurality of lines in order to accommodate many subscribers. The cablebundle generates interference. Such interference becomes an importantfactor for the ISPs because the ISPs must provide guaranteed speedsusing the cable bundle.

Therefore, there is a demand for methods for controlling or decreasinginterference occurring in the cable bundle.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the invention andtherefore it may contain information that does not form the prior artthat is already known in this country to a person of ordinary skill inthe art.

SUMMARY OF THE INVENTION

The present disclosure has been made in an effort to provide a deviceand method for decreasing interference in a cable bundle for decreasinginterference generated between a concentration device and a terminalsharing a cable bundle in an access section.

An exemplary embodiment of the present disclosure provides a device fordecreasing interference that includes: a plurality of concentrationdevices, an interference measurer. Each of conctranction devices isconnected to an uplink and configured to provide a network service to aterminal through a cable bundle in an access section. The interferencemeasurer is connected between the cable bundle and the terminal andconfigured to measure an interference signal occurring between originalsignals by measuring a signal transmitted to the terminal from theplurality of concentration devices through the cable bundle, calculatean interference coefficient for generating a quasi-interference signalfor offsetting the measured interference signal, and transmit the sameto the concentration devices. The concentration devices are configuredto calculate an additional signal for offsetting an interference signalgenerated in the cable bundle by using the interference coefficientprovided by the interference measurer, add the additional signal to theoriginal signal to be transmitted to the terminal, and transmit theadditional signal to the cable bundle.

Here, the concentration device is configured to calculate aquasi-interference signal by using the original signal and theinterference coefficient, and is configured to generate the additionalsignal by using a quasi-interference signal transmitted from a secondconcentration device for influencing a line of the second concentrationdevice for transmitting a signal.

The concentration device includes: a quasi-interference signalcalculator configured to calculate a quasi-interference signal formultiplying the original signal by the interference coefficienttransmitted from the interference measurer and transmit the same to thesecond concentration device; an additional signal calculator configuredto calculate an additional signal by using the quasi-interference signaltransmitted from the second concentration device; and a signal processorconfigured to add the additional signal calculated by the additionalsignal calculator to the original signal and transmit the same to thecable bundle.

The additional signal calculator is configured to calculate theadditional signal by adding the quasi-interference signals transmittedby the second concentration device.

The additional signal is phase-inverted from the original signal byabout 180 degrees.

Another embodiment of the present disclosure provides a method fordecreasing, by a device, interference in a cable bundle. The method mayinclude: measuring an interference signal generated between signals bymeasuring signals transmitted to a terminal from a plurality ofconcentration devices through a cable bundle, calculating aninterference coefficient for generating a quasi-interference signal foroffsetting the measured interference signal, and transmitting the sameto the plurality of concentration devices; allowing the concentrationdevices to calculate an additional signal for offsetting an interferencesignal generated in the cable bundle by using the interferencecoefficient with an original signal to be transmitted to the terminal;and transmitting a final signal calculated by adding the additionalsignal to the original signal to be transmitted to the terminal throughthe cable bundle.

Here, the calculating of an additional signal includes: allowing theconcentration devices to generate a quasi-interference signal bymultiplying the interference coefficient by the original signal andtransmit the same to a second concentration device; and calculating theadditional signal by adding the quasi-interference signal transmitted bythe second concentration device.

Yet another embodiment of the present disclosure provides a device fordecreasing interference. The device may include a plurality ofconcentration devices each connected to an uplink and configured toprovide a network service to a terminal through a cable bundle in anaccess section; and an interference measurer connected between the cablebundle and the terminal and configured to measure a signal transmittedto the terminal from the plurality of concentration devices through thecable bundle to measure an interference signal occurring betweenoriginal signals, calculate an interference coefficient for generating aquasi-interference signal for offsetting the measured interferencesignal, and transmit the same to the concentration devices, wherein theplurality of concentration devices is configured to calculate aquasi-interference signal by using the interference coefficienttransmitted by the interference measurer, and transmit the same to aconcentration device accessing an unused line, and the concentrationdevice connected to the unused line generates a final signal foroffsetting an interference signal generated in the cable bundle by usingthe quasi-interference signal transmitted by the plurality ofconcentration devices and transmits the same through the cable bundle.

Here, the concentration device multiplies the interference coefficientby the original signal to calculate the quasi-interference signal.

Further, the concentration device includes: a signal processor connectedbetween the uplink and the cable bundle and configured to perform signalprocessing so as to transmit a signal; and a quasi-interference signalcalculator configured to calculate the quasi-interference signal bymultiplying the interference coefficient transmitted by the interferencemeasurer by an original signal transmitted through the signal processorand transmitting the same to the concentration device accessing theunused line.

The concentration device accessing the unused line includes: aquasi-interference signal receiver configured to receive aquasi-interference signal from the plurality of concentration devices;and a signal processor configured to add the quasi-interference signalsfrom the quasi-interference signal receiver and calculate the finalsignal.

Yet another embodiment of the present disclosure provides a method fordecreasing, by a device, interference generated in a cable bundle. Themethod may include: measuring an interference signal generated betweensignals by measuring signals transmitted to a terminal from a pluralityof concentration devices through a cable bundle, calculating aninterference coefficient for generating a quasi-interference signal foroffsetting the measured interference signal, and transmitting the sameto the plurality of concentration devices; allowing the plurality ofconcentration devices to use the interference coefficient with anoriginal signal to be transmitted to the terminal to calculate aquasi-interference signal, and transmit the same to the concentrationdevice accessing the unused line; and allowing the concentration deviceaccessing the unused line to use the quasi-interference signaltransmitted by the concentration devices, generate a final signal foroffsetting an interference signal generated in the cable bundle, andtransmit the same through the cable bundle.

Here, the quasi-interference signal is calculated by multiplying theinterference coefficient by the original signal, and the final signal isgenerated when the concentration device accessing the unused line addsquasi-interference signals transmitted by the concentration devices.

According to embodiments of the present disclosure, the interferenceoccurring between the concentration device and the terminal sharing asame cable bundle in the access section may be decreased.

Further, the speed quality of the network service provided through thecable bundle may be accordingly improved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an interference decreasing device in a cable bundleaccording to an exemplary embodiment of the present disclosure.

FIG. 2 shows an example of a method for decreasing interference in acable bundle according to an exemplary embodiment of the presentdisclosure.

FIG. 3 shows a detailed configuration of a concentration device shown inFIG. 2.

FIG. 4 shows a flowchart of a method for decreasing interference in acable bundle according to a method shown in FIG. 2.

FIG. 5 shows another example of a method for decreasing interference ina cable bundle according to an exemplary embodiment of the presentdisclosure.

FIG. 6 shows a detailed configuration of concentration devices shown inFIG. 5.

FIG. 7 shows a detailed configuration of a concentration device shown inFIG. 5.

FIG. 8 shows a flowchart of a method for decreasing interference in acable bundle according to a method shown in FIG. 5.

FIG. 9 shows a device for decreasing interference in a cable bundleaccording to another exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In the following detailed description, only certain exemplaryembodiments of the present disclosure have been shown and described,simply by way of illustration. As those skilled in the art wouldrealize, the described embodiments may be modified in various differentways, all without departing from the spirit or scope of the presentdisclosure. Accordingly, the drawings and description are to be regardedas illustrative in nature and not restrictive, and like referencenumerals designate like elements throughout the specification.

Throughout the specification, unless explicitly described to thecontrary, the word “comprise” and variations such as “comprises” or“comprising” will be understood to imply the inclusion of statedelements but not the exclusion of any other elements. In addition, theterms “-er”, “-or”, and “module” described in the specification meanunits for processing at least one function and operation, and can beimplemented by hardware components or software components andcombinations thereof.

A device for decreasing interference in a cable bundle according to anexemplary embodiment of the present disclosure will be described withreference to accompanying drawings.

A device and method for decreasing interference in a cable bundleaccording to an exemplary embodiment of the present disclosure will nowbe described.

FIG. 1 shows a device for decreasing interference in a cable bundleaccording to an exemplary embodiment of the present disclosure.

As shown in FIG. 1, the device 10 for decreasing interference in a cablebundle includes a concentration device (e.g., concentrator) 100, aterminal 200, a cable bundle 300, and an interference measurer 400.

The concentration device 100 provides a home network service in anaccess network 10. The concentration device 100 is disposed on a side ofa network operator and connected to an uplink 500 connected to a highlevel communication device.

The terminal 200 is a terminal device of the concentration device 100.The terminal 200 is physically connected to the concentration device 100through the cable bundle 300, and the terminal 200 is disposed on a sideof a user.

The cable bundle 300 provides physical connection between at least oneconcentration device 100 and a plurality of terminals 200. The cablebundle 300 is provided as a plurality of bound cables. For example, thecable bundle 300 is configured with equal to or greater than twenty-fourpairs of bundled cables in a part of the access network.

The interference measurer 400 is disposed between the cable bundle 300and the terminal 200. The interference measurer 400 measures a signaltransmitted to the terminal 200 from the concentration device 100through the cable bundle 300. The interference measurer 400 measures aninterference signal mutually generated between original signals,calculates an interference coefficient generating a quasi-interferencesignal for offsetting the interference signal, and transmits it to theconcentration device 100.

Therefore, the concentration device 100 applies the interferencecoefficient transmitted by the interference measurer 400 to the originalsignal transmitted by the uplink 500 to generate a quasi-interferencesignal and transmit the same to the concentration device 100, and asecond concentration device 100 adds a quasi-interference signaltransmitted by a third concentration device 100 influencing a line ofthe second concentration device 100 to the original signal transmittedby the uplink 500 and transmits the same to the terminal 200 through thecable bundle 300.

In another way, the concentration device 100 applies the interferencecoefficient transmitted by the interference measurer 400 to the originalsignal transmitted by the uplink 500 to generate a quasi-interferencesignal and transmit the same to the concentration device 100corresponding to an unused line, and the concentration device 100corresponding to the unused line transmits the receivedquasi-interference signal to the cable bundle 200 through the unusedline.

Here, the interference signal caused by the original signal may beoffset when a phase of the quasi-interference signal is phase-invertedfrom the original signal by about 180 degrees.

As described, in an exemplary embodiment of the present disclosure, twomethods may be used to decrease the interference signal generated in thecable bundle 300.

Such methods will be described in further detail with reference todrawings.

FIG. 2 shows a method for decreasing interference in a cable bundleaccording to an exemplary embodiment of the present disclosure.

Referring to FIG. 2, for ease of description, the method will bedescribed with a communication environment including three concentrationdevices A (101), B (102), and C (103) respectively connected to threeterminals 201, 202, and 203 through the cable bundle 300.

When original signals transmitted to the terminals 201, 202, and 203from the concentration devices A (101), B (102), and C (103) areS_(A)(t′), S_(B)(t′), and S_(C)(t′), and the original signals aretransmitted through the cable bundle 300, the interference coefficientsmeasured and calculated by the interference measurer 400 are −α(t′),−β(t′), and −γ(t′).

Therefore, the quasi-interference signal for the concentration device A(101) represents a signal of the product of the original signal and−α(t′), the quasi-interference signal for the concentration device B(102) represents a signal of the product of the original signal and−β(t′), and the quasi-interference signal for the concentration device C(103) represents a signal of the product of the original signal and−γ(t′). The concentration device A (101) sums the quasi-interferencesignals of the other concentration devices B (102) and C (103)influencing the original signal of the concentration device A (101),adds the summed signals to the original signal of the concentrationdevice A (101), and transmits the added signals through the cable bundle300 as a final signal.

Further, the concentration device B (102) sums the quasi-interferencesignals of the other concentration devices A (101) and C (103)influencing the original signal of the concentration device B (102),adds the summed signals to the original signal of the concentrationdevice B (102), and transmits the added signals through the cable bundle300 as a final signal.

The concentration device C (103) sums the quasi-interference signals ofthe other concentration devices A (101) and B (102) influencing theoriginal signal of the concentration device C (103), adds the summedsignals to the original signal of the concentration device C (103), andtransmits the added signals through the cable bundle 300 as a finalsignal.

For example, in FIG. 2, assuming that the concentration devices A (101),B (102), and C (103) transmit the same original signals S_(A)(t′),S_(B)(t′), and S_(C)(t′), the concentration device A (101) adds thesummation signal XTALK3=S_(B)(t′)*(−β(t′))+S_(C)(t′)*(−γ(t′)) of thequasi-interference signal S_(B)(t′)*(−β(t′)) of the concentration deviceB (102) and the quasi-interference signal S_(C)(t′)*(−γ(t′)) of theconcentration device C (103) to the original signal S_(A)(t′), andtransmits the added signals to the terminal 201 through the cable bundle300.

That is, the final signal (F_(A)(t′)) transmitted to the terminal 201from the concentration device A (101) through the cable bundle 300 is asfollows.F _(A)(t′)=S _(A)(t′)+S _(B)(t′)*(−β(t′))+S _(C)(t′)*(−γ(t′))

The concentration device B (102) adds the summation signalXTALK2=S_(A)(t′)*(−α(t′))+S_(C)(t′)*(−γ(t′)) of the quasi-interferencesignal S_(A)(t′)*(−α(t′)) of the concentration device A (101) and thequasi-interference signal S_(C)(t′)*(−γ(t′)) of the concentration deviceC (103) to the original signal S_(B)(t′), and transmits the addedsignals to the terminal 202 through the cable bundle 300.

That is, the final signal (F_(B)(t′)) transmitted to the terminal 202from the concentration device B (102) through the cable bundle 300 is asfollows.F _(B)(t′)=S _(B)(t′)+S _(A)(t′)*(−α(t′))+S _(C)(t′)*(−γ(t′))

In a like manner, the concentration device C (103) adds the summationsignal XTALK1=S_(A)(t′)*(−α(t′))+S_(B)(t′)*(−β(t′)) of thequasi-interference signal S_(A)(t′)*(−α(t′)) of the concentration deviceA (101) and the quasi-interference signal S_(B)(t′)*(−β(t′)) of theconcentration device B (102) to the original signal S_(C)(t′), andtransmits the added signals to the terminal 203 through the cable bundle300.

That is, the final signal (F_(C)(t′)) transmitted to the terminal 203from the concentration device C (103) through the cable bundle 300 is asfollows.F _(C)(t′)=S _(B)(t′)+S _(A)(t′)*(−α(t′))+S _(B)(t′)*(−β(t′))

As described, in an exemplary embodiment of the present disclosure, theinterference in the cable bundle 300 may decrease by adding thequasi-interference signal for offsetting the interference signal that isgenerated when the signal transmitted through the cable bundle 300 isinfluenced by another signal to the original signal and transmitting thesame.

FIG. 3 shows a detailed configuration of the concentration devices 101,102, and 103 shown in FIG. 2. Here, the concentration devices 101, 102,and 103 have the same configuration so one concentration device 101 willbe described for ease of description.

As shown in FIG. 3, the concentration device 101 includes an uplinktransceiver 1010, a bundle-side transceiver 1011, a quasi-interferencesignal calculator 1012, an additional signal calculator 1013, and asignal processor 1014.

The uplink transceiver 1010 accesses the uplink 500 to transmit signalsto and receive the same from the uplink 500.

The bundle-side transceiver 1011 accesses the cable bundle 300 totransmit signals to and receive the same from the terminal 201.

The quasi-interference signal calculator 1012 uses the interferencecoefficient −α(t′) transmitted by the interference measurer 400 and theoriginal signal S_(A)(t′) transmitted through the signal processor 1014to calculate the quasi-interference signal S_(A)(t′)*(−α(t′)) andtransmits the same to the concentration devices 102 and 103.

The additional signal calculator 1013 receives the quasi-interferencesignals S_(B)(t′)*(−β(t′)) and S_(C)(t′)*(−γ(t′)) from the concentrationdevices 102 and 103 and calculates the additional signalXTALK3=S_(B)(t′)*(−β(t′))+S_(C)(t′)*(−γ(t′)).

The signal processor 1014 adds the additional signal (XTALK3) calculatedand transmitted by the additional signal calculator 1013 to the originalsignal S_(A)(t′) received through the uplink transceiver 1010 togenerate the final signalF_(A)(t′)=S_(A)(t′)+S_(B)(t′)*(−β(t′))+S_(C)(t′)*(−γ(t′)) and transmitsthe same to the cable bundle 300 through the bundle-side transceiver1011. The signal received from the cable bundle 300 through thebundle-side transceiver 1011 is transmitted to the uplink 500 throughthe uplink transceiver 1010.

FIG. 4 shows a flowchart of a method for decreasing interference in acable bundle according to a method shown in FIG. 2.

Referring to FIG. 4, the concentration devices A (101), B (102), and C(103) transmit the original signals S_(A)(t′), S_(B)(t′), and S_(C)(t′)to the interference measurer 400 (S100) and transmit the originalsignals S_(A)(t′), S_(B)(t′), and S_(C)(t′) to the terminals 201, 202,and 203 through the cable bundle 300 (S110).

The interference measurer 400 receives the signal transmitted throughthe cable bundle 300 to measure a channel, compares the same with theoriginal signals S_(A)(t′), S_(B)(t′), and S_(C)(t′), analyzes them(S120) to analyze the interference signal, calculates interferencecoefficients −α(t′), −β(t′), and −γ(t′) for generating thequasi-interference signal, and transmits the same to the concentrationdevices A (101), B (102), and C (103) (S130).

The concentration devices A (101), B (102), and C (103) use theinterference coefficients −α(t′), −β(t′), and −γ(t′) respectively togenerate quasi-interference signals (S140), calculate additional signalsXTALK1, XTALK2, and XTALK3 to be added to the original signals of theconcentration devices A (101), B (102), and C (103) (S150), add the sameto the original signals of the respective concentration devices A (101),B (102), and C (103) (S160), and transmit resultant signals to theterminals 201, 202, and 203 through the cable bundle 300 (S170).

Another example of a method for decreasing interference in a cablebundle according to an exemplary embodiment of the present disclosurewill now be described.

FIG. 5 shows another example of a method for decreasing interference ina cable bundle according to an exemplary embodiment of the presentdisclosure.

Referring to FIG. 5, for ease of description, the method will bedescribed with a communication environment including four concentrationdevices, A (104), B (105), C (106), and D (107) and four terminals (204,205, 206, and 207) connected through the cable bundle 300.

When the original signals transmitted to the terminals 204, 205, and 206from the concentration devices A (104), B (105), and C (106) areS_(A)(t′), S_(B)(t′), and S_(C)(t′), and the original signals aretransmitted through the cable bundle 300, the interference coefficientsmeasured and calculated by the interference measurer 400 are −α(t′),−β(t′), and −γ(t′). Here, the concentration device D (107) may be anunused concentration device that does not transmit signals or may be anadditionally supplied concentration device for the method for decreasinginterference in a cable bundle according to an exemplary embodiment ofthe present disclosure.

Therefore, the quasi-interference signal for the concentration device A(104) represents a signal of the product of the original signal and−α(t′), the quasi-interference signal for the concentration device B(105) represents a signal of the product of the original signal and−β(t′), and the quasi-interference signal for the concentration device C(106) represents a signal of the product of the original signal and−γ(t′).

That is, the concentration device A (104) calculates a signal of theproduct of the original signal of the concentration device A (104) andthe interference coefficient −α(t′) and transmits the signal to theconcentration device D (107), the concentration device B (105)calculates a signal of the product of the original signal of theconcentration device B (105) and the interference coefficient −β(t′) andtransmits the signal to the concentration device D (107), and theconcentration device C (106) calculates a signal of the product of theoriginal signal of the concentration device C (106) and the interferencecoefficient −γ(t′) and transmits the signal to the concentration deviceD (107).

Therefore, the concentration device D (107) receives the respectivequasi-interference signals from the concentration devices A (104), B(105), and C (106), adds the same, and transmits the added signals tothe terminal 207 through the cable bundle 300. In this instance, whenthe terminal 207 is not a terminal for substantially receiving thesignal or is a terminal for receiving the same, it is assumed that thecorresponding signal is not transmitted to the terminal.

For example, in FIG. 5, assuming that the concentration devices A (104),B (105), and C (106) transmit the same original signals S_(A)(t′),S_(B)(t′), and S_(C)(t′), the concentration device A (104) i) calculatesa quasi-interference signal S_(A)(t′)*(−α(t′)) that is a signal of theproduct of the original signal S_(A)(t′) and the interferencecoefficient −α(t′) and ii) transmits the same to the concentrationdevice D (107).

The concentration device B (105) i) calculates a quasi-interferencesignal S_(B)(t′)*(−β(t′)) that is a signal of the product of theoriginal signal S_(B)(t′) and the interference coefficient −β(t′) andii) transmits the same to the concentration device D (107).

In a like manner, the concentration device C (106) i) calculates aquasi-interference signal S_(C)(t′)*(−γ(t′)) that is a signal of theproduct of the original signal S_(C)(t′) and the interferencecoefficient −γ(t′) and ii) transmits the same to the concentrationdevice D (107).

As described, the quasi-interference signals transmitted to theconcentration device D (107) may be added, and the final signal(F_(D)(t′)) expressed below may be transmitted through the cable bundle300.F _(D)(t′)=S _(A)(t′)*(−α(t′))+S _(B)(t′)*(−β(t′))+S _(C)(t′)*(−γ(t′))

As described, in an exemplary embodiment of the present disclosure, theinterference signal generated in the original signal is offset and theinterference in the cable bundle 300 may decrease by transmitting thequasi-interference signal for offsetting the interference signal that isgenerated when the signal transmitted through the cable bundle 300 isinfluenced by another signal through an additional line.

FIG. 6 shows a detailed configuration of the concentration devices 104,105, and 106 shown in FIG. 5. Here, the concentration devices 104, 105,and 106 have the same configuration so one concentration device 104 willbe described for ease of description.

As shown in FIG. 6, the concentration device 104 includes an uplinktransceiver 1040, a bundle-side transceiver 1041, a quasi-interferencesignal calculator 1042, and a signal processor 1043.

The uplink transceiver 1040 accesses the uplink 500 to transmit signalsto the uplink 500 and receive the same from the uplink 500.

The bundle-side transceiver 1041 accesses the cable bundle 300 totransmit signals to the terminal 204 and receive the same from theterminal 204.

The quasi-interference signal calculator 1042 uses the interferencecoefficient −α(t′) transmitted by the interference measurer 400 and theoriginal signal S_(A)(t′) transmitted through the signal processor 1043to calculate the quasi-interference signal S_(A)(t′)*(−α(t′)) andtransmit the same to the concentration device 107.

The signal processor 1043 transmits the original signal S_(A)(t′)received through the uplink transceiver 1040 to the cable bundle 300through the bundle-side transceiver 1041. The signal received from thecable bundle 300 through the bundle-side transceiver 1041 is transmittedto the uplink 500 through the uplink transceiver 1040.

FIG. 7 shows a detailed configuration of a concentration device 107shown in FIG. 5.

As shown in FIG. 7, the concentration device 107 includes a bundle-sidetransmitter 1070, a quasi-interference signal receiver 1071, and asignal processor 1072.

The bundle-side transmitter 1070 transmits signals to the cable bundle300.

The quasi-interference signal receiver 1071 receives quasi-interferencesignals S_(A)(t′)*(−α(t′)), S_(B)(t′)*(−β(t′)), and S_(C)(t′)*(−γ(t′))from the concentration devices 104, 105, and 106.

The signal processor 1072 transmits the final signalF_(D)(t′)=S_(A)(t′)*(−α(t′))+S_(B)(t′)*(−β(t′))+S_(C)(t′)*(−γ(t′)) thatis generated by adding the quasi-interference signals received throughthe quasi-interference signal receiver 1071 to the cable bundle 300through the bundle-side transmitter 1070.

FIG. 8 shows a flowchart of a method for decreasing interference in acable bundle according to a method shown in FIG. 5.

Referring to FIG. 8, the concentration devices A (104), B (105), and C(106) i) transmit the original signals S_(A)(t′), S_(B)(t′), andS_(C)(t′) to the interference measurer 400 (S200) and ii) transmit theoriginal signals S_(A)(t′), S_(B)(t′), and S_(C)(t′) (S210) to theterminal s204, 205, and 206 through the cable bundle 300.

The interference measurer 400 receives the signal transmitted throughthe cable bundle 300 to measure a channel, compares the same with theoriginal signals S_(A)(t′), S_(B)(t′), and S_(C)(t′), analyzes them(S220) to analyze the interference signal, calculates interferencecoefficients −α(t′), −β(t′), and −γ(t′) for generating thequasi-interference signal, and transmits the same to the concentrationdevices A (104), B (105), and C (106) (S230).

The concentration devices A (104), B (105), and C (106) use theinterference coefficients −α(t′), −β(t′), and −γ(t′) respectively togenerate quasi-interference signals (S240) and transmit the generatedquasi-interference signals to the concentration device D (107) (S250).

Therefore, the concentration device D (107) adds the quasi-interferencesignals transmitted by the concentration devices A (104), B (105), and C(106) (S260) and transmits the added signals to the cable bundle 300(S270).

It has been described that, in order to offset the interference signaloccurring in the cable bundle 300, the interference coefficient measuredby the interference measurer 400 is used, and the respectiveconcentration devices 101, 102, 103, 104, 105, and 106 calculatequasi-interference signals and add the quasi-interference signals to theoriginal signals or transmit them through an additional transmissionline, but the technical range of the present disclosure is notrestricted thereto, such that interference coefficients for therespective concentration devices 101, 102, 103, 104, 105, and 106 arereceived from the interference measurer 400 and original signals arereceived from the concentration devices 101, 102, 103, 104, 105, and 106to calculate quasi-interference signals, and additional signals arecalculated based on the quasi-interference signals so that theconcentration devices 101, 102, 103, 104, 105, and 107 may transmitsignals.

For example, referring to FIG. 9, an offset signal calculator 600 isindependently provided to an additional system or one of theconcentration devices 101, 102, 103, 104, 105, and 106, and the offsetsignal calculator 600 uses the interference coefficient provided by theinterference measurer 400 and the original signals provided by theconcentration devices 101, 102, 103, 104, 105, and 106 to generatequasi-interference signals and calculate an additional signal to beadded to the original signal or an offset signal to be transmittedthrough an additional transmission line. The calculated additionalsignal may be transmitted to the concentration devices 101, 102, and 103to be added to the original signal and transmitted to the cable bundle300 or it may be transmitted to the concentration device 107 to betransmitted to the cable bundle 300 through an additional transmissionline and thereby offset the interference signal to be generated in thecable bundle 300.

While this invention has been described in connection with what ispresently considered to be practical exemplary embodiments, it is to beunderstood that the invention is not limited to the disclosedembodiments, but, on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

What is claimed is:
 1. A device for decreasing interference, comprising: a plurality of concentration devices connected to a cable bundle having a plurality of cables and configured to provide a network service to a plurality of terminals respectively connected to the plurality of concentration devices through corresponding cables of the cable bundle in an access section; and an interference measurer connected between the cable bundle and the plurality of terminals and configured to measure interference signals occurring between original signals by measuring signals respectively transmitted, through the corresponding cables of the cable bundle, from the plurality of concentration devices to the terminals, calculate interference coefficients, and transmit the interference coefficients respectively to the concentration devices, wherein one of the concentration devices is configured to receive a signal from the uplink, receive a corresponding interference coefficient from the interference measurer, generate one quasi-interference signal by applying the received corresponding interference coefficient to the received signal, and transmit the generated one quasi-interference signal to the other concentration devices, and wherein the one of the concentration device is configured to receive other quasi-interference signals from the other concentration devices, receive a transmission signal from the uplink, generate a final signal by adding the transmission signal and the other quasi-interference signals, and transmit the final signal to a corresponding terminal through the cable bundle.
 2. The device of claim 1, wherein: the plurality of concentration devices include a first concentration device, a second concentration device, and a third concentration device; and the first concentration device is configured to: i) receive a first interference coefficient from the intereference measurer, ii) receive a signal from the uplink, iii) calculate a first quasi-interference signal by multiplying received signal and the first interference coefficient, and iv) transmit the calculated first quasi-interference signal to the second concentration device and the third concentration device; and the first concentration device is configured to: a) receive a first transmission signal from the uplink, b) receive a second quasi-interference signal from the second concentration device and a third quasi-interference signal from the third concentration device, c) generate a first additional signal by adding the second quasi-interference signal and the third quasi-interference signal, d) generating a final signal by adding the first transmission signal and the first additional signal, and e) transmitting the final signal to a corresponding terminal through the cable bundle.
 3. The device of claim 1, wherein each of the plurality of concentration devices includes: a quasi-interference signal calculator configured to calculate the one quasi-interference signal by multiplying a signal from the uplink by a corresponding one of the interference coefficients from the interference measurer and transmit the calculated quasi interference signal to the other concentration devices; an additional signal calculator configured to calculate an additional signal by using the other quasi-interference signals generated by and transmitted from the other concentration devices; and a signal processor configured to generate a final signal by adding the additional signal to the signal from the uplink and transmit the final signal to a corresponding terminal through the cable bundle.
 4. The device of claim 3, wherein the additional signal calculator is configured to add the other quasi-interference signals from the other concentration devices in order to calculate the additional signal.
 5. The device of claim 3, wherein the additional signal is phase-inverted from the signal from the uplink by about 180 degrees.
 6. A method for decreasing, by one concentration device among a plurality of concentration devices coupled to a cable bundle, interference in the cable bundle, comprising: receiving a corresponding interference coefficient, wherein the corresponding interference coefficient is calculated by measuring an interference signal generated between signals based on signals transmitted from the plurality of concentration devices to terminals through the cable bundle, calculating interference coefficients respectively for the plurality of concentration devices, and transmitting the interference coefficients respectively to the plurality of concentration devices; calculating, by the one concentration device, one quasi-interference signal by using the received corresponding interference coefficient with an original signal to be transmitted to a corresponding terminal; and transmitting the calculated one quasi-interference signal to the other concentration devices coupled to the cable bundle.
 7. The method of claim 6, further comprising: receiving the other quasi-interference signals from the other concentration devices; calculating an additional signal by adding the other quasi-interference signals; generating a final signal by adding a transmission signal from the uplink and the calculated additional signal; and transmitting the final signal to a corresponding terminal through the cable bundle. 